Question

I Had a file upload control I want that file will attach only when it is below under some Memory Limit (8 Mb). I get the file size using Ajax and call it on the onchange event. But I am not able to restrict the attachment of files. Can any one Help me ?

This is the example code

function a(obj) {
    if ($(obj).val() != '') {
        var request;
        var flag = false;
        request = $.ajax({
            type: "POST",
            url: 'CheckFileSize.aspx',
            data: "search=" + $(obj).val(),
            success: function (size) {
                if (parseFloat(size) < 8192) {
                    flag = true;
                }
                if (!flag) {
                    alert('File size is greater then 8 MB. The size of the file is ' + (parseFloat(size)) / 1024 + ' MB');

//Doing something that restrict user from upload enter code here
$(obj).val(null);
}
return flag;
}
});
}
return false;
}

Answer 1

In your server-side method where you process the uploaded file, add this code:

        if (myFileUploadControl.HasFile)
        {
                int maxSize = Convert.ToInt32(ConfigurationManager.AppSettings.Get("MaxImageSize"));     //MaxImageSize specified in web.config file to make it easy to change.

                int imageSize = myFileUploadControl.PostedFile.ContentLength;
                if (imageSize > maxSize)
                {
                    string uploadImageError = "The selected file exceeds the maximum allowed size (" + maxSize / 1000 + "k)";  // Message to display to user.
                }
                else
                {
// Code to process the file here.
                }
        }

Adding the following to the system.web section of the web.config file will also prevent over-large uploads from being accepted.

<!-- set max upload to 25 MB -->
<httpRuntime executionTimeout="300" maxRequestLength="25000"/>